Vehicle traveling control device

Abstract

A control device detects a first vehicle traveling in front of an own vehicle using a front looking radar device, and detects a second vehicle which is predicted to cut in between the own vehicle and the first vehicle using the front looking radar device and/or front-side looking radar devices. The control device calculates a first target acceleration required for the own vehicle to maintain an inter-vehicle distance between the own vehicle and the first vehicle at a first set inter-vehicle distance; and calculates a second target acceleration required for the own vehicle to maintain an inter-vehicle distance between the own vehicle and the second vehicle at a second set inter-vehicle distance. The control device selects either the first target acceleration or the second target acceleration and controls the own vehicle in such a manner that an actual acceleration of the own vehicle becomes closer to the mediated target acceleration.

What is claimed is: 
     
       1. A vehicle travelling control device comprising:
 detecting means for detecting an objective-forward-vehicle traveling in front of an own vehicle and a vehicle which is predicted to cut in between said own vehicle and said objective-forward-vehicle; 
 first calculation means for calculating a first target acceleration for the own vehicle to maintain an inter-vehicle distance between said own vehicle and said objective-forward-vehicle at a first set inter-vehicle distance; 
 second calculation means for calculating a second target acceleration required for said own vehicle to maintain an inter-vehicle distance between said own vehicle and said predicted cut-in vehicle at a second set inter-vehicle distance; 
 mediation means for selecting, as a mediated target acceleration, either said first target acceleration or said second target acceleration, whichever is smaller; and 
 travel control means for controlling a driving force and a brake force of said own vehicle in such a manner that an actual acceleration of said own vehicle becomes closer to said mediated target acceleration, 
 wherein: 
 said detecting means includes
 a front looking radar device having a front looking detection area, the front looking detection area having a center axis extending in a straight forward direction of said own vehicle, the front looking radar detects a target object to obtain first target object information concerning said target object, and 
 a front-side looking radar device having a front-side detection area, the front-side detection area having a center axis extending in a diagonally forward direction of said own vehicle, the front-side looking radar detects said target object to obtain second target object information concerning said target object; 
 
 said vehicle travelling control device further comprises predicted cut-in vehicle detecting means for
 integrating said first target object information and said second target object information to obtain an integrated target object information, and detecting said predicted cut-in vehicle based on said integrated target object information, when said front looking radar device and said front-side looking radar device detect an identical target object, and 
 detecting said predicted cut-in vehicle based on said second target object information but not based on said first target object information, when said front-side looking radar device detects said target object, but said front looking radar device does not detect said target object and 
 
 said second calculation means
 calculates said first target acceleration in such a manner that said first target acceleration is allowed to be a negative acceleration achieved when a brake device of said own vehicle is operated, in a case where said predicted cut-in vehicle is detected based on said integrated target object information, and 
 calculates said first target acceleration while providing a limitation on said first target acceleration in such a manner that said first target acceleration does not become smaller than a negative acceleration achieved when a throttle valve opening of an internal combustion engine serving as a driving force of said own vehicle is set at a minimum value while said brake device of said own vehicle is not operated, in a case where said predicted cut-in vehicle is detected based on said second target object information but not based on said first target object information. 
 
 
     
     
       2. A vehicle travelling control device comprising:
 a radar system that detects an objective-forward-vehicle traveling in front of an own vehicle and a vehicle which is predicted to cut in between said own vehicle and said objective-forward-vehicle; 
 an electronic control unit configured to
 calculate a first target acceleration for the own vehicle to maintain an inter-vehicle distance between said own vehicle and said objective-forward-vehicle at a first set inter-vehicle distance, 
 calculate a second target acceleration required for said own vehicle to maintain an inter-vehicle distance between said own vehicle and said predicted cut-in vehicle at a second set inter-vehicle distance, and 
 select, as a mediated target acceleration, either said first target acceleration or said second target acceleration, whichever is smaller; 
 
 an engine electronic control unit; and 
 a brake electronic control unit; 
 wherein the engine electronic control unit and the brake electronic control unit control a driving force and a brake force, respectively, of said own vehicle in such a manner that an actual acceleration of said own vehicle becomes closer to said mediated target acceleration, 
 wherein said radar system includes
 a front looking radar device having a front looking detection area, the front looking detection area having a center axis extending in a straight forward direction of said own vehicle, the front looking radar detects a target object to obtain first target object information concerning said target object, and 
 a front-side looking radar device having a front-side detection area, the front-side detection area having a center axis extending in a diagonally forward direction of said own vehicle, the front-side looking radar detects said target object to obtain second target object information concerning said target object, and 
 
 wherein said electronic control unit is further configured to
 integrate said first target object information and said second target object information to obtain an integrated target object information, and detect said predicted cut-in vehicle based on said integrated target object information, when said front looking radar device and said front-side looking radar device detect an identical target object, 
 detect said predicted cut-in vehicle based on said second target object information but not based on said first target object information, when said front-side looking radar device detects said target object, but said front looking radar device does not detect said target object, 
 calculate said first target acceleration in such a manner that said first target acceleration is allowed to be a negative acceleration achieved when a brake device of said own vehicle is operated, in a case where said predicted cut-in vehicle is detected based on said integrated target object information, and 
 calculate said first target acceleration while providing a limitation on said first target acceleration in such a manner that said first target acceleration does not become smaller than a negative acceleration achieved when a throttle valve opening of an internal combustion engine serving as a driving force of said own vehicle is set at a minimum value while said brake device of said own vehicle is not operated, in a case where said predicted cut-in vehicle is detected based on said second target object information but not based on said first target object information.